1. Field of the Invention
The present invention relates to video game apparatuses employing an optical disk, a magnetic disk, or a semiconductor memory in which program data is recorded, which are, for example, applied to a video game apparatus using a cassette-type recording medium; model display methods for video games; and readable recording media for storing model display programs used in video games.
2. Description of the Related Art
A number of game systems have been conventionally proposed. They include a system formed of a domestic special unit and a TV monitor, and a system formed of an industrial special unit, a personal computer or a workstation, a display unit, and a sound output unit.
Any of these systems includes a controller for the user to play, a recording medium in which game program data has been stored, a CPU for controlling such that sound and images are generated according to the game program data, a processor for generating images, a processor for generating sound, a monitor for displaying images, and a speaker for outputting sound. As the recording medium, a CD-ROM, a semiconductor memory, or a cassette including a semiconductor memory is mainly used.
In such a game system, a model or a main character, displayed on the monitor as an individual entity, is three-dimensionally formed by a combination of polygons, which are virtual two-dimensional figures of a plurality of triangles or quadrangles, and is displayed as a three-dimensional image by assigning texture data, which is two-dimensional image data, to each polygon.
Therefore, in the above conventional game systems, model data formed of the coordinate data of each vertex of polygons, texture data, and texture instruction data for assigning texture data to each polygon is stored in the recording medium in advance as data which defines the model.
When models which express landforms and structures constituting a game scene are formed of a plurality of polygons three dimensionally, if models having different shapes are displayed on the monitor to give variety to the game scene, since model data needs to be specified for each model and to be stored in the recording medium, a large memory capacity is required for the recording medium. Especially when a semiconductor memory or a cassette including a semiconductor memory is used as the recording medium, it is demanded that the memory capacity required for storing model data be suppressed.
Accordingly, it is an object of the present invention to provide a video game apparatus, a model display method for a video game, and a readable recording medium for storing a model display program for a video game, which allow a game scene displayed on the monitor to show variety whereas the memory capacity of a recording medium required for storing model data is suppressed.
The foregoing object is achieved in one aspect of the present invention through the provision of a video game apparatus for displaying on display means a game scene including a model viewed from a predetermined viewpoint in a virtual three-dimensional space, the video game apparatus including model-data storage means for storing model data which defines the model; arrangement-data storage means for storing a plurality of arrangement data specified for the model and including position data in the virtual three-dimensional space; and display processing means for displaying the model on the display means by using the model data, each arrangement data, and data related to the viewpoint; and the arrangement data stored in the arrangement-data storage means differs from each other.
According to this configuration, the model data which defines the model and the arrangement data specified for the model and including the position data in the virtual three-dimensional space are stored. A plurality of arrangement data different from each other are stored. Since the model is displayed on the display means with the use of the model data, each arrangement data, and the data related to the viewpoint, the model viewed from the viewpoint is displayed at the position indicated by each position data according to each arrangement data. Therefore, models having the same shape or different shapes can be displayed at the same position or different positions, and game scenes give variety with the same model data being used.
The arrangement-data storage means may store rotation-angle data against a predetermined axis in the virtual three-dimensional space as the arrangement data.
According to this configuration, since the rotation-angle data against the predetermined axis in the virtual three-dimensional space is stored as the arrangement data, the model is displayed in a condition in which the model is rotated by the angle specified by the rotation-angle data against the predetermined axis in the virtual three-dimensional space. When the rotation-angle data of each arrangement data is set differently, models are displayed at the positions indicated by the position data in a condition in which the models are disposed in directions different from each other.
The arrangement-data storage means may store magnification data in the direction of a predetermined axis in the virtual three-dimensional space as the arrangement data.
According to this configuration, since the magnification data in the direction of the predetermined axis in the virtual three-dimensional space is stored as the arrangement data, the model is displayed in a condition in which the model is enlarged or reduced by the magnification specified by the magnification data in the direction of the predetermined axis in the virtual three-dimensional space. When the magnification data of each arrangement data is set differently, models having sizes and shapes different from each other are displayed at the positions indicated by the position data.
The video game apparatus may be configured such that the model-data storage means stores as the model data, the coordinate data of each vertex of a plurality of polygons constituting the model, a plurality of texture data, and a plurality of texture instruction data for assigning texture data to each polygon, and the display processing means includes field-of-view determination means for determining whether the position specified by each position data is located within the field of view at the viewpoint; instruction control means for outputting the data related to the viewpoint and arrangement data including the position data which specifies positions located within the field of view; conversion processing means for converting the coordinate data of each polygon according to the data output from the instruction control means; and mapping processing means for assigning the texture data specified by the texture instruction data to each polygon of which the coordinate data has been converted.
According to this configuration, the coordinate data of each vertex of the plurality of polygons constituting the model, the plurality of texture data, and the plurality of texture instruction data for assigning texture data to each polygon are stored as the model data. It is determined whether the position specified by the position data of each arrangement data is located within the field of view at the viewpoint; the data related to the viewpoint and the arrangement data including the position data which specifies positions located within the field of view are output; the coordinate data of each polygon is converted according to this output data; and the texture data specified by the texture instruction data is assigned to each polygon of which the coordinate data has been converted. Therefore, models located within the field of view can be displayed on the display means in the conditions indicated by the arrangement data.
The foregoing object is achieved in another aspect of the present invention through the provision of a model display method for a video game for displaying on display means a game scene including a model viewed from a predetermined viewpoint in a virtual three-dimensional space, the model display method including the steps of: storing model data which defines the model; storing a plurality of arrangement data different from each other, specified for the model, and including position data in the virtual three-dimensional space; and displaying the model on the display means by using the model data, each of the arrangement data, and data related to the viewpoint.
According to this method, the model data which defines the model and the arrangement data specified for the model and including the position data in the virtual three-dimensional space are stored. A plurality of arrangement data different from each other are stored. Since the model is displayed on the display means with the use of the model data, each arrangement data, and the data related to the viewpoint, the model viewed from the viewpoint is displayed at the position indicated by each position data according to each arrangement data. Therefore, models having the same shape or different shapes can be displayed at the same position or different positions, and game scenes give variety with the same model data being used.
The foregoing object is achieved in still another aspect of the present invention through the provision of a readable recording medium for storing a model display program used in a video game for displaying on display means a game scene including a model viewed from a predetermined viewpoint in a virtual three-dimensional space, the model display program including: model data which defines the model; a plurality of arrangement data different from each other, specified for the model, and including position data in the virtual three-dimensional space; and a display step of displaying the model on the display means by using the model data, each of the arrangement data, and data related to the viewpoint.
When this recording medium is read and executed by a computer, the model data which defines the model and the arrangement data specified for the model and including the position data in the virtual three-dimensional space are read. A plurality of arrangement data different from each other are stored. Since the model is displayed on the display means with the use of the model data, each arrangement data, and the data related to the viewpoint, the model viewed from the viewpoint is displayed at the position indicated by each position data according to each arrangement data. Therefore, models having the same shape or different shapes can be displayed at the same position or different positions, and game scenes give variety with the same model data being used.